Final design and construction of Avala Tower, landscape design and facility below the access platform

Realization: December 2005

The design of new tower was
prepared by Saobraćajni institut CIP in the period August - December 2005.

HISTORY

Situated in the protected
area of northernmost mountain in Šumadija at 439 m level, touristic and
telecommunication AVALA TOWER for many years was unique civil engineering
wonder designed by architects Uglješa Bogunović and Slobodan Janjić, andMilan
Krstić structural engineer and academician.

The World Federation of
Great Towers, Paris, had declared that Avala Tower was the most beautiful tower
in the world. It was the only tower in the world to have an equilateral
triangle as its cross section. For many years the experts have admired the
value of the concept and the structure and attractiveness of the composition
while the numerous visitors have admired the view from the belvedere at vast
Pannonian plain and rolling foothills of Šumadija.

More than 4000 tons of
reinforced concrete were incorporated into the structure which was constructed
in the period 1961 - 1965 on the ground above the cluster of interwining
subways and 2000-year old abandoned mining shafts. It was the tallest structure
at Balkans till 1999. This work culminated withinstallation of 60 m high
antenna which weight was about 25 tons. This USW and RTV tower enabled
broadcasting of radio program on ultra-short waves and television program which
started by the end of 1950's.

At the same time the tower
was a big telecommunication hub toward Greece, Bulgaria, Hungary and other
republics of former Yugoslavia.

The Avala TV Tower was
destroyed by NATO bombing in 1999.

PROJECT
IMPLEMENTATION - PRESENT

An action for rebuilding the
Avala Tower was initiated by the Journalists' Association of Serbia and Radio
Television of Serbia and supported by the Government of Serbia so that all
works on reconstruction of destroyed tower started in May 2005.

Many thousand tons of
remaining concrete and steel were cleared during the spring of 2005. The
clearing was followed by geodetic surveys and measurements, engineering
geological, geotechnical and geomechanical investigations and tests and soil
consolidation measures in the foundation area according to specifications for
the new Tower foundation.

More than 50 experts of
different specialties were engaged in implementation of the Final design for
reconstruction of Avala Tower. The works were executed in 2007 by "Ratko
Mitrović - Dedinje" Company according to design documentation prepared by
Saobraćajni institut CIP. The Investor's request was to maintain the visual
identity of former tower meaning that the new tower shall have same dimensions
as destroyed tower.

The concrete segment was
formed of legs, body and seven-storey gondola at the top. The tower legs were
buried by 1.4 m and supported by rock i.e. concrete block interconnected with ground
beams. The tower body has an equilateral triangle as its cross section. The
triangle sides were 7 m long measured along the wall centerline and circular
reinforcing pieces were fitted at triangle vertices. An access to tower was
enabled via reinforced concrete ramp - bridge, about 60.0 m long and 4.20 m
wide.

The seven-storey gondola at
the top of concrete segment has three closed storeys and four open storeys.

In addition to rooms and
terraces specially designed for antenna, RTV and post office devices, the Avala
Tower at level 119.20 m has coffee bar and terrace - belvedere at level 122.60
m that can be reached in less than one minute (40 seconds) by two lifts. In
case of fire, evacuation time for the tower is about nine minutes and access
control system provides insight into precise number of visitors in the tower
higher than 204 m, which was designed to withstand the strongest earthquake.

Having in mind the fact that
the former Tower was designed in 1948 before the Law on Designing in Seismic
Regions was enacted, it may be concluded that it was very challenging
assignment.

Completely new structural
analysis for the tower was elaborated, the foundation system modified and
foundation depth increased, concrete classes were enhanced to MB 60 and prestressing
tendonsinstalled in some structural members that withstand the maximum
stresses.

The special attention was
paid to fire prevention. Many materials inside the tower were substituted with
fire-resistant and non-toxic materials.

Design of lift shaft protection against
overpressure was prepared

The tower body was divided into four fire
sectors

Water fog system was designed for fire
fighting in the restaurant

The
tower structure is provided with special structural monitoring system. Results
obtained in these measurements will be used for scientific and research
purposes and for assessment of tower suitability for use in extreme weather
conditions.

Deleveled
ground beneath triangular tower base was used to form the segment under the
access plateau as new useful space of 930 m2 net area for
accommodation of related facilities intended for visitors (trade, catering,
tourism).

Supervision
of construction works on the Avala Tower complex was performed by the experts
of Saobraćajni insititut CIP.